Add pineapple, salt, turmeric powder and water in a pan and cook for 20 -25 minutes, until pineapple is cooked.
Add coconut, green chilli, ginger, cumin seeds, mustard seeds and garlic in a blender and grind to make a smooth paste.
Use little water if required to make the paste.
Add it in the pan along with pineapple and cook for another 3-4 minutes.
Add jaggery and cook for another 2-3 minutes.
Remove the pan from heat and let cool.
Once the pineapple is cooled, add whisked yogurt and mix well.
For the tadka
Heat coconut oil in a small pan.
Once the oil is hot, add mustard seeds, curry leaves and dry red chilies.
Fry for a few seconds.
Pour the tadka over the pineapple pachadi.
Serve with steamed rice, rasam and sambhar.
Notes
In order to save time for making a variety of Pachadis, you could keep the coconut masala handy. Whenever you are looking to make a variety of Pachadis, you can double or triple the amount of coconut paste which is common for all the pachadies and use as required.The coconut paste should be really smooth. Add some water if the ingredients are not grinding properly.Add the yogurt only once the curry is cooled otherwise the yogurt will separate.This pachadi tastes best when made fresh. However you can refrigerate it for a 2-3 days and microwave before eating.